Numerous types of additives are used to improve lubricating oil and fuel compositions. Such additives include, but are certainly not limited to dispersants and detergents of the ashless and ash-containing variety, oxidation inhibitors, anti-wear additives, friction modifiers, and the like. Such materials are well known in the art and are described in many publications, for example, Smalheer, et al, "Lubricant Additives", Lezius-Hiles Co., Cleveland, Ohio, USA (1967); M. W. Ranney, Ed., "Lubricant Additives", Noyes Data Corp., Park Ridge, N.J., USA (1973); M. J. Satriana, Ed., "Synthetic Oils and Lubricant Additives, Advances since 1979, Noyes Data Corp., Park Ridge N.J., USA (1982), W. C. Gergel, "Lubricant Additive Chemistry", Publication 694-320-65R1 of The Lubrizol Corp., Wickliffe, Ohio, USA (1994); and W. C. Gergel et al, "Lubrication Theory and Practice" Publication 794-320-59R3 of The Lubrizol Corp., Wickliffe, Ohio, USA (1994); and in numerous United States patents, for example Chamberlin, III, U.S. Pat. No 4,326,972, Schroeck et al, U.S. Pat. No. 4,904,401, and Ripple et al, U.S. Pat. No. 4,981,602. Many such additives are frequently derived from carboxylic reactants, for example, acids, esters, anhydrides, lactones, and others. Specific examples of commonly used carboxylic compounds used as intermediates for preparing lubricating oil additives include alkyl-and alkenyl substituted succinic acids and anhydrides, polyolefin substituted carboxylic acids, aromatic acids, such as salicylic acids, and others. Illustrative carboxylic compounds are described in Meinhardt, et al, U.S. Pat. No. 4,234,435; Norman et al, U.S. Pat. No. 3,172,892; LeSuer et al, U.S. Pat. No. 3,454,607, and Rense, U.S. Pat. No. 3,215,707.
Many carboxylic intermediates used in the preparation of lubricating oil additives contain chlorine. While the amount of chlorine present is often only a very small amount of the total weight of the intermediate, the chlorine frequently is carried over into the carboxylic derivative which is desired as an additive. For a variety of reasons, including government regulation, environmental concerns, and commercial reasons the industry has been making efforts to reduce or to eliminate chlorine from additives designed for use as lubricant or fuel additives.
Accordingly, it is desirable to provide low chlorine or chlorine free intermediates which can be used to prepare low chlorine or chlorine free derivatives for use in lubricants and fuels.
The present invention provides a method for preparing compounds which meet this requirement.
B. B. Snider and J. W. van Straten, J. Org. Chem., 44, 3567-3571 (1979) describes certain products prepared by the reaction of methyl glyoxylate with several butenes and cyclohexenes. K. Mikami and M. Shimizu, Chem. Rev., 92, 1021-1050 (1992) describe carbonyl-ene reactions, including glyoxylate-ene reactions. D. Savostianov (communicated by P.Pascal), C.R. Acad. Sc. Paris, 263, (605-7) (1966) relates to preparation of some .alpha.-hydroxylactones via the action of glyoxylic acid on olefins. M. Kerfanto et. al., C.R. Acad. Sc. Paris, 264, (232-5) (1967) relates to condensation reactions of .alpha.-.alpha.-di-(N-morpholino)-acetic acid and glyoxylic acid with olefins.